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Merge pull request #313 from greg-king5/plus4-joy 

Fix the Plus/4 (and C16) joystick driver.
This commit is contained in:
Oliver Schmidt 2016-06-18 23:23:55 +02:00 committed by GitHub
parent a7323d399e f91a7e749b
commit 520641890d
1 changed files with 18 additions and 16 deletions
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34
libsrc/plus4/joy/plus4-stdjoy.s
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@ -1,17 +1,15 @@
;
; Standard joystick driver for the Plus/4. May be used multiple times when linked
; to the statically application.
; Standard joystick driver for the Plus/4 and C16.
; May be used multiple times when linked statically to an application.
;
; Ullrich von Bassewitz, 2002-12-21
; 2002-12-21, Ullrich von Bassewitz
; 2016-06-18, Greg King
;
.include "zeropage.inc"
.include "joy-kernel.inc"
.include "joy-error.inc"
.include "plus4.inc"
.macpack generic
.macpack module
@ -26,7 +24,7 @@
; Driver signature
.byte $6A, $6F, $79 ; "joy"
.byte $6A, $6F, $79 ; ASCII "joy"
.byte JOY_API_VERSION ; Driver API version number
; Library reference
@ -39,7 +37,7 @@
.byte $02 ; JOY_DOWN
.byte $04 ; JOY_LEFT
.byte $08 ; JOY_RIGHT
.byte $10 ; JOY_FIRE
.byte $80 ; JOY_FIRE
.byte $00 ; JOY_FIRE2 unavailable
.byte $00 ; Future expansion
.byte $00 ; Future expansion
@ -98,16 +96,20 @@ COUNT:
; READ: Read a particular joystick passed in A.
;
READ: ldy #$FA ; Load index for joystick #1
READ: ldy #%11111011 ; Load index for joystick #1
tax ; Test joystick number
beq @L1
ldy #$FB ; Load index for joystick #2
ldy #%11111101 ; Load index for joystick #2
ldx #>$0000 ; (Return unsigned int)
@L1: sei
sty TED_KBD
lda TED_KBD
sty TED_KBD ; Read a joystick ...
lda TED_KBD ; ... and some keys -- it's unavoidable
cli
ldx #$00 ; Clear high byte
and #$1F
eor #$1F
rts
eor #%11111111
; The fire buttons are in bits 6 and 7. Both of them cannot be %1 together.
; Therefore, bit 6 can be merged with bit 7.
clc
adc #%01000000
rts